pub(super) fn global_zone_line_count(
gfs: &Arc<FileStore>,
zone: &str,
) -> Option<u64>Expand description
Exact non-blank line count of the output file in zone, computed via the
same streaming index builder read_range uses (so the two endpoints always
agree). Returns Some(0) for an empty file, None on read failure.
Reuses output.idx when its covered_size header already matches the
current output size — same freshness check
register_blockfile_read_range (blockfile.rs) already does — instead of
unconditionally rescanning the entire history on every call. Without this,
every pane open for an agent with any global-zone history pays a full
O(history size) rescan even when nothing has changed since the index was
last built.